He was hired by NASA's predecessor NACA in 1929 at the Langley Aeronautical Laboratory as an aerodynamicist to work on the design of the Altitude Wind Tunnel to be built in Cleveland, Ohio at the Lewis Laboratory. While at Langley, he directed important aerodynamic research which led to increased high-speed performance of most of the combat aircraft of World War II. In 1944 he joined the High-Speed panel and advocated the supersonic wind tunnel, completed in 1949. Following World War II, Silverstein was responsible for the conception, design, and construction of America's first supersonic propulsion wind tunnels. The investigations in these facilities greatly contributed to the development of supersonic aircraft. He also directed research in propulsion aerodynamics in the Altitude Wind Tunnel that led to significant improvements in both reciprocating and early turbojetaircraft engines. He also pioneered research on large-scale ramjet engines. Silverstein was placed in charge of all research at the Lewis Research Center in 1949. In 1952 he was appointed its Associate Director. He received an honorary doctorate in 1958 from Case Institute of Technology in Cleveland. At NASA Headquarters he helped create and direct the efforts leading to the space flights of Project Mercury and to establish the technical basis for the Apollo program; in particular he chaired a government commission, the Saturn Vehicle Evaluation Committee. As Lewis's director, he oversaw a major expansion of the center and the development of the Centaur launch vehicle.
Silverstein retired from NASA in 1970 in order to take a position with Republic Steel Corporation. In 1984, NASA named Silverstein an "Elder Statesman of Aviation." On August 14, 1997, he was recipient of the prestigious Guggenheim Medal for "significant contributions to the advancement of flight." Silverstein died on June 1, 2001, in his home in Fairview Park, Ohio. Silverstein is survived by two sons: Joe, of Thousand Oaks, California, and David, of Maumee, Ohio; a daughter, Judy Cook of Columbia, Maryland; and five grandchildren. His wife of 48 years, Marion Croster Silverstein, died in 1998. NASA credits Silverstein with giving both the Mercury and Apollo programs their names. In 2014, the National Aviation Hall of Fame announced that Silverstein will be inducted into the "Class of 2015" along with aviation pioneersRobert Cardenas, Robert N. Hartzell, and Gene Kranz.
